A number of common factors can be identified that influence the development and structure of the high impact weather systems. In many cases the environment in which they develop is determined by the synoptic- to planetary-scale framework associated with upper-level Rossby waves. Moist processes play a fundamental role in the development and structure of the systems as well as in their impact on the large-scale flow. The uncertainty associated with forecasts of these systems is such that the use of ensemble forecasts and adaptive observing strategies is expected to improve the information contained in forecasts. Thus PANDOWAE research focuses on research areas, the background of which is given in the following.